The first and most obvious division of the people is into
aliens and natural-born subjects. Natural-born subjects are
such as are born within the dominions of the crown of
England, that is, within the ligeance, or as it is generally
called, the allegiance of the king; and aliens, such as are
born out of it. Allegiance is the tie, or ligamen, which binds
the subject to the king, in return for that protection which
the king affords the subject. The thing itself, or substantial
part of it, is founded in reason and the nature of government;
the name and the form are derived to us from our
Gothic ancestors.

. . . . .

Allegiance, both express and implied, is however distinguished
by the law into two sorts or species, the one natural,
the other local; the former being also perpetual, the
latter temporary. Natural allegiance is such as is due from
all men born within the king's dominions immediately
upon their birth. For, immediately upon their birth, they
are under the king's protection; at a time too, when (during
their infancy) they are incapable of protecting themselves.
Natural allegiance is therefore a debt of gratitude;
which cannot be forfeited, cancelled, or altered, by any
change of time, place, or circumstance, nor by any thing
but the united concurrence of the legislature. An Englishman
who removes to France, or to China, owes the same
allegiance to the king of England there as at home, and
twenty years hence as well as now. For it is a principle of
universal law, that the natural-born subject of one prince
cannot by any act of his own, no, not by swearing allegiance
to another, put off or discharge his natural allegiance
to the former: for this natural allegiance was intrinsic,
and primitive, and antecedent to the other; and cannot
be devested without the concurrent act of that prince to
whom it was first due. Indeed the natural-born subject of
one prince, to whom he owes allegiance, may be entangled
by subjecting himself absolutely to another; but it is his
own act that brings him into these straits and difficulties,
of owing service to two masters; and it is unreasonable
that, by such voluntary act of his own, he should be able
at pleasure to unloose those bands, by which he is connected
to his natural prince.

Local allegiance is such as is due from an alien, or
stranger born, for so long time as he continues within the
king's dominion and protection: and it ceases, the instant
such stranger transfers himself from this kingdom to another.
Natural allegiance is therefore perpetual, and local
temporary only: and that for this reason, evidently
founded upon the nature of government; that allegiance
is a debt due from the subject, upon an implied contract
with the prince, that so long as the one affords protection,
so long the other will demean himself faithfully. As therefore
the prince is always under a constant tie to protect his
natural-born subjects, at all times and in all countries, for
this reason their allegiance due to him is equally universal
and permanent. But, on the other hand, as the prince affords
his protection to an alien, only during his residence
in this realm, the allegiance of an alien is confined (in
point of time) to the duration of such his residence, and
(in point of locality) to the dominions of the British empire.

. . . . .

When I say, that an alien is one who is born out of the
king's dominions, or allegiance, this also must be understood
with some restrictions. The common law indeed
stood absolutely so; with only a very few exceptions: so
that a particular act of parliament became necessary after
the restoration, for the naturalization of children of his
majesty's English subjects, born in foreign countries during
the late troubles. And this maxim of the law proceeded
upon a general principle, that every man owes natural allegiance
where he is born, and cannot owe two such allegiances,
or serve two masters, at once. Yet the children of
the king's embassadors born abroad were always held to
be natural subjects: for as the father, though in a foreign
country, owes not even a local allegiance to the prince to
whom he is sent; so, with regard to the son also, he was
held (by a kind of postliminium) to be born under the king
of England's allegiance, represented by his father, the embassador.
To encourage also foreign commerce, it was enacted
by statute 25 Edw. III. st. 2. that all children born
abroad, provided both their parents were at the time of the
birth in allegiance to the king, and the mother had passed
the seas by her husband's consent, might inherit as if born
in England: and accordingly it hath been so adjudged in
behalf of merchants. But by several more modern statutes
these restrictions are still farther taken off: so that all children,
born out of the king's ligeance, whose fathers were
natural-born subjects, are now natural-born subjects themselves,
to all intents and purposes, without any exception;
unless their said fathers were attainted, or banished beyond
sea, for high treason; or were then in the service of
a prince at enmity with Great Britain.

The children of aliens, born here in England, are, generally
speaking, natural-born subjects, and entitled to all
the privileges of such. In which the constitution of France
differs from ours; for there, by their jus albinatus, if a
child be born of foreign parents, it is an alien.

A denizen is an alien born, but who has obtained ex donatione
regis letters patent to make him an English subject:
a high and incommunicable branch of the royal prerogative.
A denizen is in a kind of middle state between an
alien, and natural-born subject, and partakes of both of
them. He may take lands by purchase or devise, which an
alien may not; but cannot take by inheritance: for his parent,
through whom he must claim, being an alien had no
inheritable blood, and therefore could convey none to the
son. And, upon a like defect of hereditary blood, the issue
of a denizen, born before denization, cannot inherit to him;
but his issue born after, may. A denizen is not excused
from paying the alien's duty, and some other mercantile
burthens. And no denizen can be of the privy council, or
either house of parliament, or have any office of trust, civil
or military, or be capable of any grant from the crown.

Naturalization cannot be performed but by act of parliament:
for by this an alien is put in exactly the same state
as if he had been born in the king's ligeance; except only
that he is incapable, as well as a denizen, of being a member
of the privy council, or parliament, &c. No bill for naturalization
can be received in either house of parliament,
without such disabling clause in it. Neither can any person
be naturalized or restored in blood, unless he hath received
the sacrament of the Lord's supper within one
month before the bringing in of the bill; and unless he also
takes the oaths of allegiance and supremacy in the presence
of the parliament.